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NUMBER 557 65
range of 1.05-1.22. Largest Japanese specimen examined (TM
(KT9015, CB1-2)) 5.85 x 5.39 mm in calicular diameter and
7.60 mm in height. Costal structure and corallum color as in N.
venustus.
Septa hexamerally arranged in 4 complete cycles, as in N.
venustus, but the relative sizes of septa differ. S1 exsert (about
1.2 mm) and have sinuous vertical inner edges that fuse with
the columella deep within fossa. S2 slightly less exsert (about
1.0 mm), two-thirds width of S,, and also have sinuous inner
edges that join with the inner P3 fusions. S3 slightly less exsert
than S2 (about 0.8 mm) and about two-thirds width of an S2,
each S3 separated by a wide notch from a tall, wide (about 0.75
mm) palus. Inner edges of each pair of P3 within a system fused
in a V-shaped structure before the S2, as in N. venustus. S4
slightly less exsert than S3 and equal to or slightly less wide
than the S3. Fossa quite shallow, containing a papillose
columella.
DISCUSSION.—Characters differentiating N. conicus from N.
venustus are listed by Cairns (1989a) and in the previous
species account. A more complete description and illustration
of this species is given by Cairns (1989a). Based on the
GCD:LCD ratio of Yabe and Eguchi's (1941c) specimen from
the Philippine Pleistocene (1.19), I now consider it to be N.
conicus, not N. venustus.
MATERIAL EXAMINED.—New Records: TM (KT9015,
CB1-2), 1, USNM 92777; TM (KT9015, HK3), 1, ORI.
Previous Records: Syntypes of C. conicus, ZMA.
TYPES.—Two syntypes of C. conicus are deposited at the
ZMA (Coel. 1185). Type Locality: Siboga-95: S^.S^,
119°40'E(Sulu Sea), 522 m.
DISTRIBUTION—Japan: Bungo Strait; off Mi Shimi, Eastern
Strait, southwestern Honshu; 70-110 m. Elsewhere:
Philippines; Makassar Strait; off Sabah, Indonesia;
34-923 m. Pleistocene of Philippines and Ryukyu Islands;
Miocene of Java (Gerth, 1921).
Peponocyathus Gravier, 1915
DIAGNOSIS.—Corallum solitary and free, but quite variable
in shape, including bowl-shaped, cylindrical, and globose.
Theca imperforate; costae serrate, corresponding to septa.
Septa highly exsert. Pali present before all but last cycle in two
crowns, but P, often suppressed. Columella papillose.
TYPE SPECIES.—Peponocyathus variabilis Gravier, 1915 (=
P. folliculus), by original designation.
Peponocyathus australiensis (Duncan, 1870)
PLATES 28c-/, 41/
Deltocyathus italicus var. australiensis Duncan, 1870:297, pi. 19: fig. 4.
Deltocyathus orientalis Duncan, 1876:431. pi. 38: Figs. 4-7.—Yabe and
Eguchi, 1932a:387, 388; 194la:418-420, text-figs. 1-3; 1941b:102;
1942b:l 12, 125-126.—Mori, 1964:314, pi. 46: figs. 1. 2.
Deltocyathoides japonicus Yabe and Eguchi, 1932a:389, fig. 3; 1937:140-141,
pi. 20: fig. 23a-c.—Eguchi. 1968:C35-36 — Eguchi and Miyawaki,
1975:57.
Not Peponocyathus orientalis Yabe and Eguchi, 1932b:444—445 [= P.
folliculus].
Deltocyathus (Paradeltocyathus) orientalis Duncan.—Yabe and Eguchi,
1937:130. 131-135.pl. 20: figs. 1-10.
Deltocyathus (Paradeltocyathus) australiensis.—Yabe and Eguchi, 1937:130.
Deltocyathoides japonicum.—Yabe and Eguchi, 1942b: 126.
Paradeltocyathus orientalis Duncan.—Eguchi, 1965:289, 2 figs.—Kikuchi,
1968:11.
Notocyathus (Paradeltocyathus) orientalis Duncan.—Eguchi, 1968:C40-41.—
Hamada. 1969:253-254. pi. 2: fig. 4a-c.—Otnuraet al.. 1984: 33. fig. IB.
Deltocyathus sp.—Eguchi, 1974:228, pi. 70: figs. 6-11.
Peponocyathus australiensis.—Cairns, 1989a:29, 30 32, pi. 14: figs, d-j; pi.
15: figs, a-d [synonymy].—Cairns and Parker, 1992:39-40, pi. 13: figs.
c-d.—Cairns and Keller, 1993:259-261.
DESCRIPTION.—Corallum bowl-shaped and small, rarely
exceeding 8 mm in calicular diameter or 7 mm in height.
Largest typical specimen examined (TM (KT9015, BS2)) only
8.6 mm in calicular diameter, but most Japanese specimens
only 5.0-6.5 mm in diameter with a relatively high H:D ratio
of 0.70-0.83. Costae rounded and equal in width (0.18-0.22
mm), separated by very thin (about 0.1 mm) and deep (up to 1
mm at calicular edge) intercostal furrows, which do not afford
a view of underlying theca. Epicenter of base 0.8-1.0 mm in
diameter and granular, from which 6 independent C1 originate.
Within every system the C2 and 2 C3 originate in a trifurcation
at the border of the epicentral region. Only 0.5 mm beyond this
region a pair of C4 split from each C3. Corallum white.
Septa invariably hexamerally arranged in 4 complete cycles
(48 septa). S1 easily distinguished by their highly exsert upper
margins and greater width, each having a straight, vertical inner
edge that almost reaches the columella. S2 less exsert and about
three-quarters width of an Sv each usually bearing a small (0.5
mm wide) lamellar paliform lobe, the 6 P2 forming a palar
crown encircling columella. S3 about three-quarters width of an
S2 and often bear 1-3 papillose paliform lobes, positioned
slightly outward from the columella with resepect to P2 crown.
S4 adjacent to S1 usually slightly wider than those adjacent to
S2. All septal and palar faces highly granular. Fossa shallow.
Columella papillose, composed of up to 12 cylindrical,
granular elements.
DISCUSSION.—I (Cairns, 1989a) synonymized Deltocyathoides
japonicus with Peponocyathus australiensis, but did not
explain why. Specimens of the D. japonicus growth form
invariably result from asexual regeneration of a parent
fragment, which is easily recognized by the incorporation of the
parent fragment into the new corallum (Plate 2%d,e). Specimens
of this form are usually larger than typical specimens and have
more septa (e.g., 72 septa in holotype of GCD 15.1 mm); have
taller costal spines; and have much wider intercostal spaces,
allowing a view of the underlying theca. Their septal symmetry
is irregular, their palar structure is often rudimentary, and the
columella is often lacking. In general, these specimens have a
poorly organized structure typical of a juvenile corallum, even
though they are among the largest specimens of the species.
Because this morphology was believed to be the result of
asexual fragmentation of P. australiensis, it was synonymized